Everything Scuba

Dual cave dive with an incredible sunset while snorkeling in Dubrovnik, Croatia on the famous, stunning, sensational Dalmatian Coast of the Adriatic Sea – James Graff, Grant Kelly and Jeff Graff – Cannon Power Shot SD 950 Is Digital Elph in a waterproof case

Cave diving is a type of technical diving in which specialized SCUBA equipment is used to enable the exploration of natural or artificial caves which are at least partially filled with water. It is an extension of the more common sport of caving, but is much more rarely practised because of the skills and equipment required, and because of the high potential risks.

Despite these risks, water-filled caves attract cavers and speleologists due to their often unexplored nature, and present divers with a technical diving challenge. Caves often have a wide range of unique physical features, such as stalactites and stalagmites, and can contain unique flora and fauna not found elsewhere.

Safety

Most cave divers recognize five general rules or contributing factors for safe cave diving, which were popularized, adapted and became generally accepted from Sheck Exley’s 1977 publication Basic Cave Diving: A Blueprint for Survival In this book, Exley included accounts of actual cave diving accidents, and followed each one with a breakdown of what factors contributed to the accident. Despite the uniqueness of any individual accident, Exley found that at least one of a small number of major factors contributed to each one. This technique for breaking down accident reports and finding common causes among them is now called Accident Analysis, and is taught in introductory cave diving courses. Exley outlined a number of these resulting cave diving rules, but today these five are the most recognized:

* Training: A safe cave diver never exceeds the boundaries of his/her training. Cave diving is normally taught in segments, each segment focusing on more complex aspects of cave diving. Furthermore, each segment of training must be coupled with real world experience before moving to a more advanced level. Accident analysis of recent cave diving fatalities has proven that academic training without sufficient real world experience is not enough should an emergency occur underwater. Only by slowly building experience can one remain calm enough to recall their training should a situation arise, whereas an inexperienced diver (who may be recently trained) —will tend to panic when confronted with a similar situation.

* Guide line: A continuous guide line is maintained at all times between the leader of a dive team and a fixed point selected outside the cave entrance in open water.[2] Often this line is tied off a second time as a backup directly inside the cavern zone. As the dive leader lays the guideline he takes great care to ensure there is sufficient tension on the line. Should a silt out occur, divers can find the taut line and successfully follow it back to the cave entrance. It is important to note that not using a guide line is the number one cause of fatality among untrained, non-certified divers who venture into caves.

* Depth rules: Gas consumption and decompression obligation increase with depth, and it is critical that no cave diver exceeds the dive plan or the maximum operating depth (MOD) of the gas mixture used.[2] Also, the effects of nitrogen narcosis are possibly greater in a cave, even for a diver who has the same depth experience in open water. Cave divers are advised not to dive to “excessive depth,” and to keep in mind this effective difference between open water depth and cave depth. It should be noted that among fully trained cave divers, not paying sufficient attention to depth is the number one cause of fatality.

* Air (gas) management: The most common protocol is the ‘rule of thirds,’ in which one third of the initial gas supply is used for ingress, one third for egress, and one third to support another team member in the case of an emergency.

* Lights: All cave divers must have three independent sources of light. One is considered the primary and the other two are considered backup lights. If ANY ONE of the three light sources fail for one diver, the dive is called off and ended for all members of the dive team.

These five rules may be remembered with the mnemonic The Good Divers Are Living, the first letter of each word referring to the first letter of the corresponding rule.